Disc drives are common data storage devices. A typical disc drive includes a rigid housing that encloses a variety of disc drive components. The components include a plurality of discs having data surfaces that are coated with a medium for storage of digital information in a plurality of circular, concentric data tracks. The discs are mounted on a spindle motor that causes the discs to spin and the data surfaces of the discs to pass under the aerodynamic bearing of the sliders. The is sliders carry transducers, which write information to and read information from the data surfaces of the discs.
To increase recording density, it has become desirable to reduce the fly height over the disc. However, during disc drive operation, the volume of air in the head disc interface (HDI) should be void of contaminants. Serious damage to the disc and a loss of data can result if particles become present in the head disc interface (HDI). Contaminants, such as particles loosely held to the drive components can dislodge and enter the air stream. For example, particles in the HDI can cause performance problems such as media defects, thermal asperities, sanction, or catastrophic drive failure. Further, particles in the HDI can reach the trailing edge (TE) of the slider and damage the sensitive read/write transducers. Even if the disc drive was built free of contaminants, particles can generate whenever at least two disc drive components come in contact.
Disc drives contain filtration systems to protect the disc from these particles. A filtration system generally contains sub-systems such as a recirculation filter, a carbon adsorber, a breather filter and a diffusion path. In addition, air dams and air guides are positioned between the discs to push air from the central axis of the discs towards the recirculation filter and to laminate the airflow. In spite of the use of a variety of different kinds of filtration systems, a portion of the air in the air stream never makes it to the recirculation filter and is recirculated between the discs. This make up air can contain contamination and recirculate over the disc many times before escaping a shroud that surrounds the discs.
Embodiments of the present invention provide solutions to these and/or other problems and offer other advantages over the prior art.